The invention relates to the field of vehicle-related electronics, and, more particularly to vehicle alert systems and related methods for alerting a user when away from the vehicle.
Vehicle security systems are widely used to deter vehicle theft, prevent theft of valuables from a vehicle, deter vandalism, and to protect vehicle owners and occupants. A typical automobile security system, for example, includes a central processor or controller connected to a plurality of vehicle sensors. The sensors, for example, may detect opening of the trunk, hood, doors, windows, and also movement of the vehicle or within the vehicle. Ultrasonic and microwave motion detectors, vibration sensors, sound discriminators, differential pressure sensors, and switches may be used as sensors. In addition, radar sensors may be used to monitor the area proximate the vehicle.
The controller typically operates to give an alarm indication in the event of triggering of a vehicle sensor. The alarm indication may typically be a flashing of the lights and/or the sounding of the vehicle horn or a siren. In addition, the vehicle fuel supply and/or ignition power may be selectively disabled based upon an alarm condition.
A typical security system also includes a receiver associated with the controller that cooperates with one or more remote transmitters typically carried by the user as disclosed, for example, in U.S. Pat. No. 4,383,242 to Sassover et al. and U.S. Pat. No. 5,146,215 to Drori. The remote transmitter may be used to arm and disarm the vehicle security system or provide other remote control features from a predetermined range away from the vehicle. Also related to remote control of a vehicle function U.S. Pat. No. 5,252,966 to Lambropoulous et al. discloses a remote keyless entry (RKE) system for a vehicle. The RKE system permits the user to remotely open the vehicle doors or open the vehicle trunk using a small handheld transmitter.
Unfortunately, the majority of vehicle security systems need to be directly connected by wires to individual vehicle devices, such as the vehicle horn or door switches of the vehicle. In other words, a conventional vehicle security system is hardwired to various vehicle components, typically by splicing into vehicle wiring harnesses or via interposing T-harnesses and connectors. The number of electrical devices in a vehicle has increased so that the size and complexity of wiring harnesses has also increased. For example, the steering wheel may include horn switches, an airbag, turn-signal and headlight switches, wiper controls, cruise control switches, ignition wiring, an emergency flasher switch, and/or radio controls. Likewise, a door of a vehicle, for example, may include window controls, locks, outside mirror switches, and/or door-panel light switches.
In response to the increased wiring complexity and costs, vehicle manufacturers have begun attempts to reduce the amount of wiring within vehicles to reduce weight, reduce wire routing problems, decrease costs, and reduce complications which may arise when troubleshooting the electrical system. For example, some manufacturers have adopted multiplexing schemes to seduce cables to three or four wires and to simplify the exchange of data among the various onboard electronic systems as disclosed, for example, in xe2x80x9cThe Thick and Thin of Car Cablingxe2x80x9d by Thompson appearing in the IEEE Spectrum, February 1996, pp. 42-45.
Implementing multiplexing concepts in vehicles in a cost-effective and reliable manner may not be easy. Successful implementation, for example, may require the a development of low or error-free communications in what can be harsh vehicle environments. With multiplexing technology, the various electronic modules or devices may be linked by a single signal wire in a bus also containing a power wire, and one or more ground wires. Digital messages are communicated to all modules over the data communications bus. Each message may have one or more addresses associated with it so that the devices can recognize which messages to ignore and which messages to respond to or read.
The Thompson article describes a number of multiplexed networks for vehicles. In particular, the Grand Cherokee made by Chrysler is described as having five multiplex nodes or controllers: the engine controller, the temperature controller, the airbag controller, the theft alarm, and the overhead console. Other nodes for different vehicles may include a transmission controller, a trip computer, an instrument cluster controller, an antilock braking controller, an active suspension controller, and a body controller for devices in the passenger compartment.
A number of patent references are also directed to digital or multiplex communications networks or circuits, such as may be used in a vehicle. For example, U.S. Pat. No. 4,538,262 Sinniger et al. discloses a multiplex bus system including a master control unit and a plurality of receiver-transmitter units connected thereto. Similarly, U.S. Pat. No. 4,055,772 to Leung discloses a power bus in a vehicle controlled by a low current digitally coded communications system. Other references disclosing various vehicle multiplex control systems include, for example, U.S. Pat. No. 4,760,275 to Sato et al.; U.S. Pat. No. 4,697,092 to Roggendorf et al.; and U.S. Pat. No. 4,792,783 to Burgess et al.
Several standards have been proposed for vehicle multiplex networks including, for example, the Society of Automotive Engineers xe2x80x9cSurface Vehicle Standard, Class B Data Communications Network Interfacexe2x80x9d, SAE J1850, July 1995. Another report by the SAE is the xe2x80x9cSurface Vehicle Information Report, Chrysler Sensor and Control (CSC) Bus Multiplexing Network for Class xe2x80x98Axe2x80x99 Applicationsxe2x80x9d, SAE J2058, July 1990. Many other networks are also being implemented or proposed for communications between vehicle devices and nodes or controllers.
Unfortunately, conventional vehicle security systems for hardwired connection to vehicle devices, such as aftermarket vehicle security systems, are not readily adaptable to a vehicle including a data communications bus. Moreover, a vehicle security system if adapted for a communications bus and devices for one particular model, model year, and manufacturer, may not be compatible with any other models, model years, or manufacturers. Other systems for remote control of vehicle functions may also suffer from such shortcomings.
Yet another shortcoming of vehicle security systems to the extent they may be compatible with a vehicle having a data communications bus, is that such systems provide only a local indication of an alarm trigger, for example. Accordingly, should the user be unable to hear the alarm indication at the vehicle, such as when the user is in an adjacent building, the user is not alerted to the alarm and can take no preventive action.
In view of the foregoing background, it is therefore an object of the present invention to provide a system and method for alerting a user when away from the vehicle regarding vehicle security or other vehicle-related information when the vehicle includes a data communications bus.
This and other objects, features and advantages in accordance with the present invention are provided by a vehicle alerting system comprising at least one device at the vehicle, such as for generating security signals on the data communications bus, a remote receiver to be carried by a user, a local transmitter at the vehicle, and a paging controller at the vehicle. The paging controller is connected to the local transmitter and data communications bus. The paging controller is for causing the local transmitter to transmit to the remote receiver based upon security signals on the data communications bus to thereby alert the user when away from the vehicle.
The system may further include an indicator connected to the remote receiver for providing an indication to the user relating to security of the vehicle. For example, the indicator may comprise at least one of an audible, visual, or tactile indicator.
The at least one security device may comprise at least one of a door switch, trunk switch, hood switch, motion sensor, and proximity sensor. Alternately or in addition, the at least one security device may comprise a security controller. For the security controller, the security signals generated may be at least one of an alarm signal and a security controller status signal. For example, the security signals could relate to triggering of the alarm, or changing the status of the security controller from an armed to disarmed mode or vice-versa.
The system may also include a remote transmitter to be carried by the user, and a local receiver at the vehicle connected to the security controller for receiving signals from the remote transmitter. In a variation, a common housing may contain both the remote transmitter and the remote receiver.
In some embodiments, the transmission from the local transmitter to the remote receiver may be a direct path. In other embodiments, at least one additional communications link may be provided for relaying signals from the local transmitter to the remote receiver.
Another optional aspect of the invention relates to adaptability to a variety of vehicles, or, more particularly, to different signal sets for different vehicle makes or models. In other words, the paging controller may include desired signal enabling means for causing the local transmitter to transmit to the remote receiver based upon predetermined signals for a corresponding desired vehicle from a plurality of sets of signals for different vehicles. The desired signal enabling means may comprise a memory for storing a plurality of sets of signals for different vehicles, and a selector for selecting predetermined signals from the plurality of different sets of signals for different vehicles. The selector may include a user selector for permitting a user to select the predetermined signals. In other embodiments, the desired signal enabling means may comprise bus learning means for learning the predetermined signals based upon signals on the data communications bus. The desired signal enabling means may also comprise download learning means for learning the predetermined signals from a downloading device.
A method aspect of the invention is for alerting a user when away from a vehicle. The vehicle is preferably of a type comprising a data communications bus, and at least one device at the vehicle for generating signals on the data communications bus. The method preferably comprises the steps of providing a remote receiver to be carried by the user, and installing a paging unit in the vehicle. The paging unit preferably includes a local transmitter and a paging controller connected thereto for causing the local transmitter to transmit to the remote receiver based upon signals on the data communications bus.